Traffic on the Internet has quickly grown and continues to expand at unprecedented rates. Network devices, such as network switches, play a critical role in sustaining that growth. Data to be passed by switches is generally divided into a series of packets that can be transmitted between devices. Packets include control information and payload data. The control information includes information used to deliver the payload data. For example, control information can include source and destination network addresses, packet sequencing identification, error detection codes, and the like.
Generally, network devices have two primary planes: a control plane and a data plane. The control plane is a management plane that configures the data plane. The data plane receives packets on input ports and transmits the received packets to output ports based on the configuration. Communication between the control plane and data plane can be accomplished through a communications bus (e.g., PCIe).
A network link includes a physical interconnection (e.g., a cable) between network devices, as well as layer 1 hardware (e.g., an Ethernet card) and possibly other hardware in the data plane of the network device (e.g., layer 2 and layer 3 hardware).
Network traffic monitoring can be used to check for errors in the network links by requesting error information from network devices and checking if the errors exceed threshold levels. However, if network traffic on the link is low, it is difficult to test the network links efficiently and errors often go unnoticed.